I have the model from before that (st-2000, I think?). Worked great until it broke all of a sudden. We use it when we're motoring or in super light air. When motoring it's loud, and in super light air the boat is banging around anyway.
They're the standard model in our charter
fleet as well. Haven't heard anything specifically wrong with them other than the "you'll get a few years out of them, probably" type of thing. Regarding displacement
, you can go heavier provided you don't use it for nasty conditions. Steering
a 15 ton boat that's motoring along on glass conditions uses less power than a 10 ton that's sailing in swells.